Error Code: - P0171

[Graf1x]

Eror Code P0171
System too Lean(Bank 1),

Been talking to different people about it and they have suggested the MAF sensor being a bit dodgy and also the PVC valve or DV valve might be causing the issue.

When the EML isn't on the car is running really well (And faster) and then after around 2-3 hours of driving power drops again and then It appears the the fault code comes up as pending.

It's going into VW on Saturday to change the PVC valve and DV valve so will hopefully see if that fixes it.

Just writing on here too see if you guys can offer any advice on what I could do to resolve the issue.

Would love to hear your thoughts!

 

[KebabWarrior81]

This may help buddy

Possible Causes:

Mass Air Flow Sensor (G70) defective
Intake System Leak(s)

Possible Solutions:

Check Mass Air Flow Sensor (G70)
Check Fuel Pressure Regulation
Check Fuel Pump
Check Injectors
Check Intake System for Leaks
Check Exhaust System for Leaks
Check Secondary Air System for Leaks
Check Vacuum Pipes for Leaks

 

[Graf1x]

Thanks matey,

I've seen a similar list when I was googling the problem as well. Going to get the guys at VW to check for leaks in the air flow and get the above parts changed as well.

Was thinking about changing the MAF sensor but my mate at VW said that it's very uncommon to find the MAF sensor to fail on 2.0 TFSI engines.

Will just have to wait and see I guess!

 

[KebabWarrior81]

No problem buddy, perhaps the MAF sensor would benifit from a clean rather than spend the money on a new one if that is the issue.

Keep us posted on what was the cause once sorted mate.

Cheers

Craig

 

[MJ]

The fault refers to the ecu ruling that the air to fuel ratio is out and there's too much air being taken into the engine. This could be an external air leak or an internal leak on the intake.

external could be a damaged pipe or split intercooler for example.

internal could be an issue with the breather system, usually the pcv valve or a split diaphragm on the DV but then again you'd get poor performance all the time.

 

[Graf1x]

The fault refers to the ecu ruling that the air to fuel ratio is out and there's too much air being taken into the engine. This could be an external air leak or an internal leak on the intake.

external could be a damaged pipe or split intercooler for example.

internal could be an issue with the breather system, usually the pcv valve or a split diaphragm on the DV but then again you'd get poor performance all the time.

Cheers for the input, well the DV and the PCV valves will be getting changed on Saturday, will get them to take a look for any damaged pipes and to take a look at the intercooler as well.

Would the MAF sensor being damaged or dirty cause this code to pop up aswell?

 

[MJ]

It's not an issue I've come across.

The ecu uses the maf, map and lambda sensors to judge AFRs so it could be an issue on any part of the systems monitored by them.

 

[Graf1x]

It's not an issue I've come across.

The ecu uses the maf, map and lambda sensors to judge AFRs so it could be an issue on any part of the systems monitored by them.

Hopefully replacing the PCV and DV valve will resolve this issue then!

 

[Atteman]

did it?